Airbus A320 ATA 12 (Technical Notes)

ATA 12 – SERVICING

• GENERAL
  • Ground Service Connections
  • NO STEP Areas
  • Drainage Points

• REPLENISHING – SERVICING
  • Fuel
  • Hydraulic System Reservoir
  • Landing Gear Shock Absorber Hydraulic Fluid
  • Engine Oil
  • IDG Oil
  • Starter Oil
  • THS Actuator Oil
  • RAT Oil
  • HYD Accumulator – N2
  • BRK Accumulator – N2
  • Tires – N2
  • Landing Gear Shock Absorber – N2
  • Water
  • LAV Soap
  • Waste (Toilet)
  • Rain Repellent

• SCHEDULED SERVICING
  • External Cleaning
  • Internal Cleaning
  • THS Actuator Ball Screw Nut Lubrication
  • Flap Track 1 Drive Lever Arm and all Carriage Rollers on all Flap Tracks Lubrication
  • Spoiler No 1 to 5 Actuator Attachments Lubrication
  • All Track Rollers and Pinions Lubrication
  • MLG, NLG, Doors, Uplocks Lubrication
  • FWD, AFT & BULK Cargo Door Seal Lubrication
  • Cargo Doors Lubrication
  • Doors External Handles Lubrication
  • THS Bearings and Attachment Fittings Lubrication
  • Rudder Hinge Bearing No. 6 Lubrication

• UNSCHEDULED SERVICING
  • De-icing
  • Drain water content from fuel
  • Fuel Sampling for water contamination
  • Test for water contamination in fuel
  • Pre-conditioning

• AIRCRAFT GROUNDING (EARTHING)

Ground Service Connections

• Lavatory Service Door
• Potable Water Service Door (AFT & CTR)
• External Power Receptacle
• Ground Service Conditioned Air Connection
• HP Air Ground Connector
• Hydraulic System Ground Service Panels (3 – G, Y, B)
• Engine Oil Filling Connector (Gravity & Pressure)
• Refuel/Defuel Coupling
• Gravity Filling Panels (LH & RH)
• Refuel/Defuel Control Panel
• APU Oil Filling Connector

NO STEP Areas

It is permitted to walk on the THS in the center section only to use a protective mat of 3/8 inch thick rubber. It is not permitted to walk on the leading/trailing edges and the tips.

Drainage Points

• DRAIN MAST WATER – FWD & AFT
• DRAIN MAST FUEL – CTR
• FUEL WATER DRAIN – 8
• POTABLE WATER DRAIN – FWD & CTR
• POTABLE WATER FULL DRAIN – AFT
• WASTE DRAIN – AFT

REPLENISHING – SERVICING

FUEL

• Refer to AMM CH. 20 for data on the types of fuel that can be used.
• General Refuel/Defuel Safety Procedures – The procedure that follows contains information as specified in the IATA Guidance Material on Standard Into-Plane Fueling Procedures.

• Bonding & Grounding (Earthing)
• Chocks position – Make sure that the chocks do not touch the tires. The weight of the fuel can lower the aircraft and cause the chocks to catch.
• If possible – set breaks
• If MLG doors open – sufficient clearance.
• Correct fire-x
• Correct fuel – flight manual
• In emergency – refuel with one engine running (Ref. FCOM)
• APU start – permitted if normal, not permitted if fails to start or auto shutdown.
• Vent – clear
• Fuel Tanker/ hydrant – move away quickly in emergency
• Do not refuel/defuel in bad weather conditions and electrical storms. Lightning is dangerous.
• Do not operate aircraft’s external lighting.
• Do not fill the oxygen system or change the oxygen bottles.
• Do not refuel if a fire or engine overheat warning is displayed on the flight deck.
• Do not use the microphone on the High Frequency (HF) transmitter during refuel/defuel operations.
• Refuel/defuel zone – 10ft (3m) radially (aircraft filling and venting points)
• GPU operation – 10 feet from aircraft filling and venting points.
• Photographic flash bulbs or electronic flash – 10 feet
• Weather radar operation – 60m from nose.
• Do not refuel/defuel less than 30m from radar or HF radio operation.
• NO SMOKING – 15m from the refuel/defuel equipment and aircraft and aircraft tank vents.

For Hangar

• Open all the hangar doors.
• Do not close the hangar doors until you have completed the refuel/defuel procedure.
• To be prepared to tow the aircraft out of the hangar for an emergency.

Pressure Refueling

• Pressure Refuel with Automatic Control
• Pressure Refuel with Manual Control
• Pressure Refuel with Manual Plunger (if refuel v/v not working)

• PRESELECTED rocker switch (Pre-Selector).
• +/- 100 kg uplifted fuel.
• Get a fuel sample from the aircraft and measure its actual density.
• Make sure that a fuel sampling for water contamination check is done to the fuel in the fuel tanker/pump unit.
• After the refuel control-panel access-door is opened, if you use refuel battery power only:
  • It is not possible to start the refuel sequence for approximately 35 to 40 seconds. // because FQIC & FLSS BITE sequences operate first.
• Airbus recommends you not to keep the door open longer than necessary because the battery power decreases.
• Make sure that you do the refuel panel test before the refuel procedure or before the fuel tank is 70 percent full. Defective high-level sensors can cause fuel to spill overboard.
• Before you do refuel procedure, make sure that:
  • All the fuel pumps are off, or
  • Fuel pumps are on with mode sel pushbutton switch in the auto position.
• If the fuel pumps are on and the mode sel pushbutton switch is not in the auto position, there is a risk that fuel will spill.
• Before you close the crossfeed valve, make sure that the fuel pumps are off. This will prevent damage to the crossfeed valve.
• Before you start the wing tank pumps, make sure that:
  • There is a minimum of 750 kg of fuel in the applicable wing tanks, and
  • The mode sel pushbutton switch is in the auto position.
  • This will prevent dry running and subsequent damage to the wing and center tank pumps.
• Do not let the refuel pressure be more than the maximum pressure of 50 psi. If you do not obey this instruction, damage to the aircraft or equipment can occur.
• Make sure that the handle of the refuel coupling cap points aft when the cap is closed and locked.
• When refueling is complete do a discrepancy check.
• If you do not have ground power available: – On the refuel/defuel control panel, put the BATT POWER switch to the ON position and release. The HOT BUSS is energized for ten minutes only (this is to prevent discharge of the aircraft batteries), unless you put the MODE SELECT switch (on the refuel/defuel panel) to REFUEL.
• When you refuel the aircraft with battery power, it is not always possible to refuel to full capacity. This is because the intercell transfer valves are not always in the correct position.

Pressure Refuel without Electrical Power

• Release the Magnetic Level Indicators (MLI)
• Use the MLIs to monitor the quantity of fuel in each tank.
• Push and hold in the manual plunger on the refuel valve.
• Make an entry in the aircraft technical log, to check the fuel configuration before the subsequent flight.

Magnetic Level Indicators (MLI)

• DO NOT LET THE MLI’s FALL FREELY.
• Find and write down the aircraft attitude figure (pitch and roll data) as follows:
  • use the ADIRU to find the aircraft attitude figure, or,
  • use the FQIC input parameters to find the aircraft attitude figure.
• MLI are accurate to +/- 5% of their indication. This is not sufficiently accurate to use them as a datum for the Fuel Quantity Indication (FQI).

HYDRAULIC

• The aircraft hydraulic systems are filled with hydraulic fluids with a phosphate ester base.
• The hydraulic fluid is specified by the operator. All fluids agree with the NSA 307110 specification. You can mix them.
• To monitor the hydraulic fluid, it is necessary to get samples frequently, count particles (physical contamination) and examine the filter clogging indicators.
• If the filter clogging indicator is shown, you must:
  • Stop the related hydraulic system.
  • Replace the clogged filter.
  • Get a sample of the hydraulic fluid from the system and send it for analysis.
• Use the results of the analysis record (physical contamination) to do the reclamation of the hydraulic fluid.
• The in-service limits for hydraulic fluid properties are:
  • The physical properties,
  • The chemical properties.

Hydraulic System Reservoir – Hydraulic Fluid Servicing

• Fill the Hydraulic Fluid Reservoir with a Hand Pump.
• If the hydraulic reservoir is too full, adjust the fluid level accurately. It is not necessary to drain the hydraulic reservoir fully.
• Configuration –
  • speed brakes and spoilers are retracted
  • thrust reversers are stowed (closed)
  • landing gear is extended and landing gear doors are closed.
  • One main landing gear door may be kept open.
  • FWD and aft cargo-compartment doors are closed.
  • All the other hydraulically controlled systems are in the normal position.
  • Hydraulic systems are depressurized.
  • Do not depressurize the system reservoirs.
• The correct hydraulic quantity depends on the reservoir temperature.
• The cockpit reservoir full level is permitted to be above the normal full limit, if the reservoir level has been adjusted before or the reservoir gauge on the ground service panel is according to the HYDRAULIC RESERVOIR FILLING CAPACITIES.

Landing Gear Hydraulic Servicing – AMM ATA 12

L/G Fluid – When each aircraft landing-gear shock absorber is supplied, it is filled with a hydraulic fluid that agrees with the MIL-H-5606 or MIL-PRF-5606 specification.

OIL

ENGINE OIL (A320/CFM56)

Check oil level and replenish
+ Check Pop Out Indicator of EMCD (Electrical Master Chip Detector)

• Do not remove the filler cap of the oil tank immediately after engine operation. Let the oil pressure decrease for a minimum of 5 minutes after the engine shutdown. If you open the filler cap when there is pressure in the tank, the oil can burn you dangerously.
• In order to reduce burden for nuisance EMCD pop out indication, the inspection of the Electrical Master Chip Detector can be deferred to the next convenient maintenance opportunity where trained personnel can perform the inspection without interfering with revenue service operation.
• Oil should be added not less than 5 minutes and not more than 60 minutes after engine shutdown while the oil in the tank is still warm. This will prevent the over-servicing of the engine.
• If the oil in the tank is cool or cold, the oil density will increase (volume decreases) and the oil tank can be over-serviced.
• If the oil tank is over-serviced, this will not damage the engine. The extra oil will be blown overboard through the engine vent system.
• The quantity of oil can cause incorrect calculations for the consumption rate.
• Clean the oil tank scupper before you remove the oil tank filler cap, to prevent contamination of the tank during servicing.
• Do a check for fuel in the oil.
• Before you add oil in the oil tank during its servicing, make sure the oil in the tank does not contain fuel. If it smells of fuel, replace the main oil/fuel heat exchanger and servo fuel heater then flush the engine oil system.
• If you think there are fuel fumes when you remove the oil filler cap, do a check for fuel in the oil. If there is fuel in the oil tank, replace the main oil/fuel heat exchanger and the servo fuel heater then flush the engine oil system.
• If you think there is fuel in the oil, use one of the following available on-site test kits to examine the oil:
  • VISCOMETER – Measuring the viscosity of the oil,
  • DETECTOR-COMBUSTIBLE GAS – Checking for presence of a combustible vapor.
• If the test fails then fuel is found, do these steps:
  • Replace the Main Oil/Fuel Heat Exchanger 
  • Replace the Servo Fuel Heater 
• If the test passes, no fuel is found.
• Add engine oil by pouring into the oil tank fill port up to full mark.
• Before you install oil tank filler cap, ensure that the O’ring seal is in good condition or does not show signs of leakage. If not, replace the O’ring seal.
• Make sure that the oil tank filler-cap is locked. its handle must point to the oil quantity transmitter.
• Make sure that the filler cap is correctly closed. if it is not correctly closed, a bad supply pressure of the oil lubrication unit during engine operation can occur.
• Make sure that the work area is clean and clear of tools and other items. Close the oil tank access door.

IDG OIL

• Depressurization of the IDG Case – Connect the overflow drain hose.
• Do a check of the IDG oil brand on the placard. If not then install the placard as per IPC.
• AMM 20 gives a list of approved oil brand-names for the IDG servicing.
• Stop this filling procedure when the minimum quantity of oil collected from the overflow drain hose is 0.95 L.
• The IDG oil temperature is shown on the ECAM “ELEC SD” page.
  • If the oil temperature is less than 49 DEG.C (120 DEG.F), the oil is cold.
  • If the oil temperature is equal to or more than 49 DEG.C (120 DEG.F), the oil is hot.
• Inspection of the IDG oil level after an engine run (recommended procedure) or a dry motoring (alternative procedure).
• If you dry motored the engine or did an idle power test, make sure that the oil level is stable before you do the inspection. the oil level becomes stable only after a period of:
  • 30 minutes if you dry-motored the engine, or
  • 5 minutes if you did an idle power test.
• If you add oil when it is not necessary, failure of the IDG can occur.
• After the oil level correction, no more dry motoring or idle power test is necessary.
• Oil Level
  • Cold Condition  – AT or NEAR the line b/w yellow and green band.
  • Hot Condition – Oil level must be in the yellow band.

STARTER OIL

• Measure the quantity of the drained oil.
• If the oil quantity is more than 0.5L, the starter is serviceable.
• If the quantity is less than 0.5L, replace the starter.
• Make sure that the thread of the starter drain port is in good condition. a bad condition of the thread can cause an important oil leakage.
• The quantity of oil used will be less than 0.8L.

GAS (NITROGEN)

Precaution: Do not let compressed gas touch your skin. The gas can go through the skin and make bubbles in the blood. This condition can kill you.

Hydraulic Power Accumulators

• Depressurize the applicable hydraulic system (G, B, Y).
• Wait for approx 1 minute to make sure that the pressure in the bladder is stable.
• TORQUE charging valve nut & blanking cap.
• Temp vs Pressure table.
• 25°C – 1930 PSI

Brake Pressure Accumulator (Part of Y HYD Sys)

• Make sure that the pressure in the brake accumulator of the Yellow hydraulic system is released.
  • Operate the manual depressurization button on the brake relief valve to release the pressure.
• Before Charging – Wait for 25 minutes to let the pressure become stable and get a more accurate value (temperature compensation of the brake accumulator).
• Charging rate – less than 725 psi per minute.
• Temperature vs Pressure graph.
• 25°c – 1030 PSI
• After Charging – Wait for five minutes (with the pressure regulated supply connected and the control valve open) to let the brake accumulator temperature and pressure become stable.
• TORQUE the nut of the charging valve.
• You must not use too much force when you tighten the nut of the charging valve. Leakage from the charging valve can occur if the valve seat is damaged.
• do a leak check of the charging valve.
• TORQUE the cap.

Nitrogen Filling of the Tires

• Use only dry nitrogen or other inert gases to inflate the tires on the main gear wheels.
• The oxygen in the gas used to inflate these tires must not be more than 5% (volume).
• If the aircraft is far from its base and no dry nitrogen is available, you can use air for the servicing of the tires if:
  • The oxygen in the tires is not more than 5% (volume), or
  • Maintenance personnel remove the air from the tires and inflate them with dry nitrogen before 15 hours time service.
• A chemical reaction between the oxygen in the tires and gases from the inner liner can cause a tire explosion.
• Airbus recommends that when you inflate the tires, you must use the maximum pressure of the normal pressure range. This will decrease the number of times the tires are deflated.
• Loaded is for the aircraft weight on the wheels.
• Unloaded is when the applicable wheel is lifted on jacks.
• Unloaded pressure will be approx 7 PSI less than Loaded.
• Loaded pressure as per MTOW : (Normal – Maximum) – there is no minimum value, It is either normal or maximum.

• Do a visual inspection of the tire inflation valve and the tire inflation valve-cap. Make sure that their threads are not damaged.
• Leak check.
• If the tire inflation valve-cap has flats, TORQUE it to between 4.42 and 8.85 lbf.in.
• If the tire inflation valve-cap is knurled, fully tighten it.

WATER

Fill the Potable Water Tank System

• Do not do work on the toilet waste system and the potable water system at the same time. This will prevent contamination of the potable water system. Such contamination can be dangerous to health.
• Make sure that the water pressure is not more than 50.0 psi. If the water pressure is more than 50.0 psi, damage to equipment can occur.
• Turn the FILL/DRAIN handle to the PULL TO FILL position, then pull it out to the mechanical stop.
• The OVERFLOW VALVE OPEN light comes on.
• If the OVERFLOW VALVE OPEN light does not come on – Examine the position of the overflow valve.
• The “Overflow valve open” light on the service panel must be off when the overflow valve is closed.
• If electrical power is not available –
  • On the Drain and Overflow Panel: Turn the TANK OVERFLOW handle to the OPEN position.
  • On the Service Panel: Turn the FILL/DRAIN handle to the PULL TO FILL position, Then pull it out to the mechanical stop.
  • Operate the water service vehicle and fill the potable water tank until water comes from the TANK OVERFLOW port.
• Visually examine the connections for leaks. Leaks are not permitted.

LAVATORY

• Servicing of the Liquid Soap Dispenser – AMM

Servicing of the Toilet System

Draining

• Make sure that the vacuum pressure is not more than 6 psi maximum, if you use a vacuum operated toilet service vehicle. a higher vacuum pressure can cause damage to the vacuum toilet system.
• Connect the 4-inch diameter drain hose to the toilet drain connection.
• When you close the drain cap, the inner flap will close and lock automatically.

Flushing

• Connect the 1-inch flush/fill hose of the toilet service vehicle to the fill and rinse connection(s).
• Flush the waste tank with a maximum of 57L of water with a pressure value between 35 psi and 50 psi.

RAIN REPELLENT

Inspection/Check of the Level and Pressure of the Rain Repellent Fluid – ATA 12

• If there is leakage of FORALKYL 2211, you can smell a pine odor.
• On the pressure indicator, make sure that the pointer points to the green area – if the pointer points to the yellow area, the can should be replaced at the next opportunity.
• On the quantity indicator, make sure that there is sufficient rain-repellent fluid – if you see the surface of the fluid, replace the can.

Servicing of the Rain Repellent Fluid Can – ATA 30

• Make sure that you depressurize the rain repellent system before you remove the rain repellent fluid-can.
• Rain repellent fluid can come out suddenly if you remove the fluid can with the system pressurized.
• Connect Drain-Hose/Bottle to the drain valve.
• Push the pushbutton of the rain-repellent fluid-gage assembly to depressurize the system.
• Make sure that the fluid does not stay on the aircraft furnishing.
• If the fluid gets on the aircraft furnishings, clean with Non Aqueous Cleaner – Isopropyl Alcohol.
• Do not torque the retaining collar screw of the clamp to more than its maximum torque value of 17.70 lbf.in. If you do, you can cause damage to the can.

SCHEDULED SERVICING

CLEANING

• External Cleaning (Exterior Cleaning)
• Internal Cleaning (Deep Cleaning)
  • Cleaning of the Cockpit Equipment/Furnishings
  • Cleaning of the Cockpit Display-Units
  • Disinfection of the Aircraft Equipment and Furnishing
  • Disinsection of the Aircraft Equipment and Furnishings

LUBRICATION – 27

• Grease
  • MIL-PRF-23827 Type I or II
  • SAE AMS 3052
  • NYCO GREASE GN 148 – Mostly Use
  • MOBILGREASE 33
  • AEROSHELL GREASE 33

• Lubricate THS Actuator Ball Screw Nut
  • Grease can come out from the ball-screw nut vent hole or the top/bottom nut seals.
  • If the grease leaks from a different position, you must replace the THS Actuator.
  • Cycle the THS – Up & down
• Lubricate Flap Track 1 Drive Lever Arm and all Carriage Rollers on all Flap Tracks
• Lubricate Spoiler No 1 to 5 Actuator Attachments
  • Make sure that the grease comes out on each side of the spherical bearings:-
  • If the grease comes out from the greaser, extend the related spoiler.
  • Lubricate the spoiler servo-control bearings through the greaser until the grease comes out on each side of the spherical bearings.
  • Do the operational test of the spoiler hydraulic actuation.
• Lubricate all Track Rollers and Pinions
  • Lubrication of Slat-Track Pinion Bearings, Slat Track Rollers, Pinions and Rack Teeth
  • Use a BRISTLE BRUSH to lubricate the pinions and the rack teeth.

LUBRICATION – 32

• MLG, NLG, Doors, Uplocks

GREASE

• NYCO GREASE GN 148 – Mostly Use
• MOBILGREASE 33
• AEROSHELL GREASE 33
• SAE AMS 3052
• MIL- PRF-23827 Type I or II
• MIL-PRF-81322

MLG – 64

MLG DOOR – 3

MLG UPLOCKS – 9

NLG – 55

NLG DOOR – 11

NLG UPLOCKS – 7

Use the hand-operated lubrication equipment to lubricate the uplock with a maximum of two full strokes.

Do an inspection of the chrome surfaces of the actuator piston rods. Make sure that there is no grease on the chrome surfaces of the actuator piston rods.

• If you find grease on the chrome surfaces of the actuator piston rods, Clean the chrome surfaces with a clean LINT-FREE COTTON CLOTH (SAE AMS 3819) made moist with the Non Aqueous Cleaner – Petroleum Based (MIL-PRF-680). 
• Apply a thin layer of the Phosphate Ester Hydraulic Fluid (PE-5/LD-4/500B-4/HYJET V) with a clean Textile-Lint free Cotton on the chrome surfaces of the actuator piston rods.

LUBRICATION – 52

FWD, AFT & BULK Cargo Door Seal

• Clean with LINT-FREE COTTON CLOTH (SAE AMS 3819) made moist with Non Aqueous Cleaner-Non structural (CITRA SAFE (BAC 5750) use.
• Lubricate with Vaseline/Petrolatum/Petroleum jelly

Cargo Door

• MIL-PRF-7870 (OIL) 
• NYCO GREASE GN 148 – Mostly Use
• MOBILGREASE 33 
• AEROSHELL GREASE 33 
• MIL- PRF-23827 TYPE I 
• SAE AMS 3052 

Doors External Handles

• Pax & Cargo Door
  • MOLYKOTE 33 M
• BULK Cargo Door
  • NYCO GREASE GN 148 – Mostly Use
  • MOBILGREASE 33 
  • AEROSHELL GREASE 33 
  • MIL- PRF-23827 TYPE I or II
  • SAE AMS 3052
• Avionics Compartments
  • MOLYKOTE 55 M

LUBRICATION – 53

THS Bearings and Attachment Fittings

Configuration

• Hydraulic systems – depressurized.
• Pitch-trim control wheels – zero.
• Install pitch-trim control locking tools on the pitch-trim control wheels.

Grease

• NYCO GREASE GN 148 – Mostly Use
• MOBILGREASE 33 
• AEROSHELL GREASE 33 
• MIL- PRF-23827 TYPE I 
• SAE AMS 3052

STABILIZERS – 55

Lubrication of Rudder Hinge Bearing No. 6

Grease

• MIL-PRF-23827 Type I or II
• SAE AMS 3052
• NYCO GREASE GN 148 – Mostly Use
• MOBILGREASE 33
• AEROSHELL GREASE 33

UNSCHEDULED SERVICING

DE-ICING

• The ice protection procedures and all the data related to de-icing/anti-icing fluids are given in the SAE standards available on the website www.sae.org:
  • SAE AS 6285 (Aircraft Ground De-Icing/Anti-Icing Processes).
  • SAE AS 6286 (Training and Qualification Program for De-Icing/Anti-Icing of Aircraft on the Ground).
• The data given in the amm procedure are guidelines only. The operators can use these guidelines and their experience and knowledge of the local weather conditions to help them to make the decisions.
• It is the responsibility of the operators to make the decision about the applicable protection procedures.

FUEL – Drain & Sampling

1. Drain water content from fuel
2. Sampling for water contamination
3. Test for water contamination

Drain Water Content

• If possible, Airbus recommends you to do the water drain procedure before the flight or the refuel procedure. If you do this procedure after the flight or the refuel procedure, you must wait for one hour for the separation of the water and the fuel.
• It is permitted to do this procedure when the APU is in operation only if the fuel tank pumps are set to OFF.
• For the gravity procedure, Airbus recommends that there must be more than 10% content of the fuel in each tank.
• If you have less than 10% content of the fuel, then the indirect water drain valves will have a decreased flow.
• It is recommended that you use the suction procedure when you have less than 10% content of the fuel.
• The surge tanks are the temporary tanks that are made to collect fuel that can overflow from the vent lines. Usually, no fuel can be drained from the surge tanks.

Fuel Sampling for Water Contamination

• Put the fuel sample into a CONTAINER-CLEAN, STERILIZED, TRANSPARENT GLASS or CONTAINER-FUEL RESISTANT, TRANSPARENT PLASTIC. If you do not do the analysis immediately, seal the container.
• Do the sample removal procedure at all the water drain valves.
• Examine the water drain valve for fuel leakage – If the water drain valve does leak, use the TOOL – PURGING to push (in) and release (out) the center of the valve three or four times.
• Make sure that there are no leaks.

Water Contamination Test

• Let the sample become stable:
• If the sample moves into two layers it contains water. Continue to drain from the water drain valve until it has no water.
• If the sample stays in one layer, it can be all fuel or all water. To find if the sample is fuel or water, do the test that follows:
• If you have a HYDROKIT available, put the contents into the sample.
  • If the powder stays white, the sample is fuel and the test is complete.
  • If the white powder changes color to purple, the sample is water. Continue to take the samples and test it until the water drain valve has no water.
• If you do not have a HYDROKIT available, add water to the sample.
  • If the sample moves into two layers, then the sample is all fuel and the test is complete.
  • If the sample stays in one layer, then the sample is water. Continue to take the samples and test it until the water drain valve has no water.
• You can use the same procedure to do an analysis on a sample from a fuel tanker. You can remove the sample from the supply connector of the fuel tanker.
• To discard the water samples, refer to the local regulations.

PRE-CONDITIONING

• LP ground connection – With electrical power & without electrical power. Without electrical power – only for maintenance, if required, otherwise use other methods.
• HP ground connection
• APU
• PCA Unit – Subfreezing PCA Unit through LP ground connection provides air to the cabin with a temperature below the freezing point during operation in hot weather conditions.
  (PCA – Pre-conditioned Air)
• Do not use conditioned air from the apu or high-pressure ground unit at the same time as air from the low-pressure ground unit. If you do not obey this precaution, damage to the check valves or the aircraft can occur.
• After the APU starts, Airbus recommends you to wait for a minimum of 3 minutes (a warm-up period for the APU) before you select the APU BLEED pushbutton switch.

GROUNDING POINTS

• Grounding (earthing) – a/c to earth
• Bonding – equipment to a/c
• Grounding (Earthing) Cable – that has a section of 22 mm² (0.034 in.²) or more.
• Static electricity from the flight or the environmental conditions on ground (wind with dust, sand, etc.) is discharged through the tires.
• Tire contact with the ground is sufficient for electrostatic discharge but not for electrical safety (grounding/earthing).
• You must electrically ground (earth) the aircraft when in storm conditions.
• During the maintenance, it is recommended to do the grounding (earthing) of the aircraft.
• During the refuel/defuel or oxygen servicing operations – Bonding is mandatory.

During transit, it is not necessary to ground (earth) the aircraft when you do maintenance tasks with equipment that is supplied with electrical power from:

• The aircraft electrical system (Auxiliary Power Unit (APU), engine or battery) or
• An external power source (Ground Power Unit (GPU)) or
• Battery.

Transit refers to an aircraft during its regular operations and includes overnight stops when the aircraft is at a terminal gate or on the ramp.

DO NOT WEAR A HEADSET OR TOUCH CABLES/LINES CONNECTED TO THE AIRCRAFT, DURING BAD WEATHER CONDITIONS. LIGHTNING IS DANGEROUS.